This class represents the chess board itself.

	copying
	copy copyBoard: postCopy

	hashing
	hashKey hashLock updateHash:at:from:

	initialize
	initialize initializeNewBoard resetGame

	moving
	movePieceFrom:to: nextMove: nullMove undoMove:

	printing
	printOn:

	accessing	top
	activePlayer
	blackPlayer
	generator
	searchAgent
	searchAgent:
	statusString
	userAgent
	userAgent:
	whitePlayer

	copying	top
	copy Answer another instance just like the receiver. Subclasses typically override this method; they typically do not override shallowCopy.
	copyBoard: Copy all volatile state from the given board
	postCopy

	hashing	top
	hashKey
	hashLock
	updateHash:at:from:

	initialize	top
	initialize
	initializeNewBoard
	resetGame

	moving	top
	movePieceFrom:to:
	nextMove:
	nullMove
	undoMove:

	printing	top
	printOn: Append to the argument, aStream, a sequence of characters that identifies the receiver.

	class initialization	top
	initialize ChessGame initialize
	initializeHashKeys ChessGame initialize